Book def is Any long molecule composed of small repeating units bonded together.

Amino acid

A small organic molecule with a central carbon atom bonded to an amino group, a carboxyl group, a hydrogen atom and a side group. Proteins are polymers of 20 common amino acids. (side chain is what differs between types of amino acid)

Peptide bond

covalent bond between carboxyl group of one amino acid and the amino group of the amino acid next to it. (Covalent Bond)

4 basic levels of organization of protein structures.

Primary

Secondary

Tertiary

Quaternary

Primary Structure

sequence of amino acids (order matters)!!

What if primary structure changes?

Each amino side chain has specific properties. The change of a single amino acid would change the function. Example is sickle cell disease.

Secondary Structure

results from hydrogen bonding between the carboxyl oxygen of one amino acid and the amino hydrogen of another. This is where the structure starts to becomes more 3-d like.